<input [(ngModel)]="searchTitle" (keyup.enter)="handleSearch()">
<button (click)="handleSearch()">搜索</button>

<ul>
  <li [ngClass]="{'hover': hoverTitles[item.id]}"
    *ngFor="let item of articles" (click)="handleClick(item.id)">
    {{item.id}}-{{item.title}}-{{item.content}}
  </li>
</ul>